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Crowe's ejection of rapper 'justified'

Russell Crowe has been portrayed as the hero, not villain in the Beverly Hills Hotel fracas with Azealia Banks after the pint-sized rapper allegedly threatened to cut his and a female party guest's throats with a broken glass.

The Los Angeles District Attorney's office announced on Wednesday they would not pursue charges against the New Zealand-born Oscar winner.

Banks had accused Crowe of grabbing her by the neck, spitting on her and using a racial slur at the October 15 star-studded gathering in Crowe's suite, but prosecutors said Crowe's actions were "justified to prevent imminent violence threatened by" the rapper.

"We declined to file charges against Russell Crowe due to a lack of sufficient evidence," LA District Attorney spokesman Ricardo Santiago told AAP.

An investigation was launched after New York-born Banks reported the incident to the Beverly Hills Police Department about 12 hours after the 3am clash with Crowe.

Prosecutors, in their "charge evaluation worksheet" obtained by AAP, point to witness statements from party attendees who backed Crowe and portrayed Banks as "the assaultive party".

"Witnesses state that prior to being ejected from the hotel room by Crowe, Banks repeatedly used a racial epithet, was verbally aggressive to party attendees and threatened to break a glass to cut the throat of a female and/or Crowe," prosecutors wrote.

"It was then that Crowe escorted Banks out of the room.

"DDA (prosecutors) concludes a trier of fact would find the physical escort out of the room was justified to prevent the imminent violence threatened by Banks."

The 182cm tall Crowe, 52, reportedly put the 160cm Banks, 25, in a bearhug and carried her out of the suite.

Prosecutors also deemed it would be inappropriate to "hold Crowe criminally accountable for the minor battery of spitting on Banks' gloved hand, when as here, it was incidental to preventing more serious threatened violence".

"A witness at the door states the saliva did not make contact with Banks," prosecutors wrote.

"Witnesses describe Banks as likely impaired by alcohol and/or drugs.

"Banks admits making insulting statements to Crowe prior to the escort out.

"Banks had no visible injuries when she reported the incident to police on a delayed basis, approximately 12 hours later.

"There is no known hotel video of the doorway or in the hotel."

The incident reportedly flared when Banks criticised Crowe's music selection and described Crowe and another guest as "boring white men".